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Issue: Vol. 5717 No. 2: 5 Nov. 2025
Type: Article
Published: 2025-11-05
DOI: 10.11646/zootaxa.5717.2.2
Page range: 180-206
Abstract views: 135
PDF downloaded: 10

A new species of Dixonius Bauer, Good, and Branch, 1997 (Squamata: Gekkonidae) ranging through the Cardamon Mountains of Cambodia to the southern Mekong Delta of Vietnam

Herpetology Laboratory, Department of Biology, La Sierra University, 4500 Riverwalk Parkway, Riverside, California 92505, USA; Department of Herpetology, San Diego Natural History Museum, P.O. Box 121390, San Diego, California 92112 USA
Wild Earth Allies, 77a, Street Beton, Bayap Village, Sangkat Phnom Penh Thmei, Khan Sen Sok, Phnom Penh, Cambodia
Institute of Life Sciences, Vietnam Academy of Science and Technology, 9/621 Vo Nguyen Giap Highway, Linh Xuan Ward, Thu Đuc City, Hochiminh City, Vietnam
Herpetology Laboratory, Department of Biology, La Sierra University, 4500 Riverwalk Parkway, Riverside, California 92505, USA
Indochina Southeast asia gekkonid integrative taxonomy endemism Reptilia

Abstract

A new species of the gekkonid genus Dixonius from the Cardamom Mountains of southern Cambodia and the southwestern Mekong Delta region of Vietnam is delimited based on a molecular phylogeny comprised of 1,396 base pairs of the mitochondrial gene ND2 and diagnosed by statistically significant size-corrected morphometric, meristic, and color pattern characteristics. The new species, D. luuhoangorum sp. nov., is the sister species of D. sambhupura from approximately 200 km to the northwest in Kratie Province, eastern Cambodia. The highly fragmented topography through which this species ranges is mirrored by its peculiar phylogeographic relationships where some of the geographically proximate northern Cardamom Mountain populations are more closely related to the Mekong Delta populations of southwestern Vietnam. The description of D. luuhoangorum sp. nov. continues to underscore the localized endemism within this genus and the necessity for continued systematic based fieldwork in both well-explored and under-explored regions of Indochina in order to establish conservation measures.

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How to Cite

Grismer, L.L., Neang, T., Tri, N.V. & Grismer, J.L. (2025) A new species of Dixonius Bauer, Good, and Branch, 1997 (Squamata: Gekkonidae) ranging through the Cardamon Mountains of Cambodia to the southern Mekong Delta of Vietnam. Zootaxa, 5717 (2), 180–206. https://doi.org/10.11646/zootaxa.5717.2.2